Speaker system



June 20, 1967 J. T. VALUCH 3,326,321

SPEAKER SYSTEM Filed April 4, 1966 [/w E/vroe.

United States Patent 3,326,321 SPEAKER SYSTEM John T. Valuch, 1083 45th Way, Long Beach, Calif. 90807 Filed Apr. 4, 1966, Ser. No. 539,985 8 Claims. (Cl. 181-31) This invention relates to improved loud speaker systems, and more particularly to speaker systems having a plurality of speaker cones, whether used individually or for the production of stereophonic effects.

Conventional audio speaker systems, including so-called stereophonic or stereo systems, are incapable of providing audible sound waves of a given volume at various audio frequencies that, upon radiating outwards, will produce substantially equal volumes of sound at all points in the circumference of a given circle having the speaker system located in the circles center.

Particularly with respect to relatively high audio frequencies, such conventional speaker systems are unable to provide proper external guidance of sound waves and thereby cause audible variances in volume of a given volume of sound as it radiates outwards and reaches various points in the circumference of a given circle having the speaker system located in the circles center.

Further, such conventional speaker systems fail to provide a flat response of audio frequencies over a range of about 25 to about 16,000 cycles per second.

Moreover, conventional stereophonic systems are limited in their production of a completely balanced stereophonic effect to a point located at a 45 angle to each of the two speakers used in such systems. Thus, a completely balanced stereophonic effect occurs only at a position located at the apex of a cone having an angle of 45, more or less, formed by lines of equal length' each ending at a respective speaker of the stereophonic system. Further, at points within the cone, but not at the apex of the cone, such conventional stereo systems fail to produce a completely balanced stereo effect, although some stereo effect is produced within the cone, in that one or the other of the two speakers predominates in volume of sound, thereby producing an unbalanced stereo effect.

Nevertheless, hardly any stereo effect is produced at points outside of the cone mentioned previously, let alone at each point in the circumference of a circle drawn with the speakers at the center of the circle.

It is, therefore, an object of my invention, to provide a speaker system which will produce sound waves of a given volume that will prevent substantial variances in volume at various audio frequencies upon radiating outwards at all points in the circumference of a given circle having the speaker system located in the circles center.

Another object of my invention is to provide a speaker system which will produce an essentially flat response from about 25 cycles to about 16,000 cycles per second.

A further object of my invention is to provide a speaker system which, when used as a pair, will produce a completely balanced stereo effect of audible sound waves of uniform volume at all points in the circumference of a circle having the pair of speaker systems located at its center.

A still further object of my invention is to provide a speaker system which, when used as a pair, will produce .a completely balanced stereo effect without limiting the location of the stereo effect to a cone-shaped area between the two speakers.

A yet further object of my invention is to provide a speaker system having the foregoing characteristics but that is nevertheless relatively easy to manufacture and to assemble. I

Patented June 20, 1967 These and other objects will be more readily understood by reference to the following drawing, in which FIGURE 1 is a perspective view in elevation of the speaker enclosure of my invention.

FIGURE 2 is an elevational section of the speaker enclosure illustrating the components contained therein.

FIGURE 3 is a cross section taken on line 33 of FIGURE 2.

FIGURE 4 is a cross section taken on line 4-4 of FIGURE 2.

My improved speaker system has an enclosure body referred to as element 10 in the drawing, having a conventional full range speaker 12 and a conventional high frequency speaker or tweeter 14 located in special separation within the enclosure body 10. Suitable full range speakers may vary from about 8 to 15 inches in diameter or more, with an essentially fiat frequency from about 20 to about 8000 or 9000 cycles per second. Suitable tweeters may vary from about 5 to about 6 inches in diameter so long as the audio range covers from about 2000 to about 16,000 cycles, with an essentially flat frequency response at the higher frequencies.

The full range speaker 12 may be preferably of the open type, and need not be completely enclosed on the inside of enclosure body 10. However, the tweeter 14, for optimum results, should be of the closed type, or else be completely enclosed on the inside of enclosure body 10.

The speaker 12 and tweeter 14 in each enclosure body 10 are preferably arranged to radiate sound in opposite directions from each other, the speaker 12 facing vertically downwards and the tweeter 14 facing vertically upwards.

The distance between the full range speaker 12 and the tweeter 14 is not critical so long as sufiicient distance is maintained to prevent any interference between the two.

The open end of speaker 12 is attached to a lower plate 16 having a relatively large central opening 18 and smaller circumferential openings or slots 20 to guide reinforcing sound waves from the back of speaker 12. The space provided by said opening 18 and slots 20 may vary preferably from 60 to of the area of the diaphragm of the speaker 12, so long as the speaker characteristics are matched thereby.

A lower guide cone 22 is located in the central opening 18 of lower plate 16 with the top portion of the cone extending up into speaker 12. Guide cone 22 is preferably formed in a generally hyperbolic shape with a peaked top portion. In conjunction with lower plate 16, the outer surface of guide cone 22, the surface facing into enclosure body 10, forms a uniquely shaped channel 23 for passage of sound waves from speaker 12 and out of enclosure body 10 uniformly in all directions surrounding the enclosure body. Channel 23 also provides relatively rapid flow of large volumes of sound, due to its shape and to the peaked top portion of guide cone 22.

The outer flared edge 24 of lower guide cone 22 is attached by any suitable means to the base 26 of enclosure body 10. Lower cone spacers 28 maintain a properly spaced distance of the lower guide cone 22 with respect to speaker 12 and connect the sides of enclosure body 10 to the base 26. The distance between the outer flared edge 24 of lower guide cone 22 and the outer edge of the speaker 12 should be preferably in a ratio of about 1 to 6 with reference to the diameter of speaker 12. Thus, the diameter of the speaker 12 should preferably be about 6 times the distance between the outer flared edge 24 of lower guide cone 22 and the outer edge of speaker 12, for best results. However, this ratio may vary plus or minus 25% without materially changing the operation of my invention.

Since all of lower cone spacers 28 together need take up less than 4% of the total space available between the outer circumference of lower plate 16 and the outer circumference of the base 26, lower cone spacers 28 have only inconsequential, if any, effect on the passage of sound from full range speaker 12.

The base 26 is supported by feet 30 as shown in the drawing, but said feet are unnecessary for the acutal operation of my invention.

Although the drawing illustrates an enclosure body having the shape of a hexagon, any suitable form of enclosure body may be used in my invention. a

My invention provides for shielding within the enclosure body to prevent reflected waves therein. Any suitable material may be used, so long at about 50% of the inside portion of the sides of enclosure body 10 are shielded with such material. Although the drawing illustrates such mate rial 32 lining three adjoining inside walls of enclosure body 10, the material need not be continuous from one side to another, and individual portions of material may be separated from one another, so long as sufficient material is used to provide the required shielding.

The high frequency speaker or tweeter 14 is located at the top of enclosure body 10 and is attached to an upper plate 34 with open end 36 facing upwards. The lower portion of upper plate 34 is lined with shielding material similar to that used for the inside portion of the sides of the enclosure body 10, to prevent reflected waves.

A speaker holding ring 38 maintains the open end 36 of tweeter 14 in position against recesses 40 in upper plate 34.

An upper guide cone 42 is located with its top extending downwards into the open end 36 of tweeter 14 and with its flared outer end secured to the top 44 of enclosure body 10. The upper cone 42 is preferably formed with its sides having a generally parabolic shape and with a peaked top.

The upper cone 42 is generally flatter in overall construction than the lower cone 22 because it handles higher frequencies.

In conjunction with upper plate 34, the outer surface of upper guide cone 42, the surface facing into enclosure body 10, forms a uniquely shaped channel 45 for the passage of sound waves from tweeter 14 and out of enclosure body 10 uniformly in all directions surrounding enclosure body 10.

Upper cone spacers 46 maintain a properly spaced distance between the upper cone 42 and the open end 36 and support the top 44 of enclosure body 10. The distance between upper cone 42 and the open end 36 of tweeter 14 should be preferably in the ratio of 1 to 4 with reference to the diameter of tweeter 12, for best results. Thus, the diameter of the tweeter 14 should preferably be about 4 times the distance between upper cone 42 and the open end 36 of tweeter 14. However, this ratio may be varied plus or minus 25% without materially affecting the operation of my invention.

Since all of upper cone spacers 46 together need take up less than 4% of the total space available between the outer circumference of the top 44 and the outer circumference of upper plate 34, upper cone spacers have only inconsequential, if any, effect, on the passage of sound from the tweeter 14.

A conventional capacitor 48 of suitable capacity, such as 12 rnicrofarads, is connected to the speaker system to keep low frequencies out of tweeter 14.

Speaker connection 50 provides means for hooking the speaker system to an amplifier (not shown).

The outer base portion of enclosure body 10 may be covered with speaker grille cloth 52 for improved appearance. The top portion of the enclosure body 10 may be covered by perforated decorative tape 54, or other material permitting unobstructed passage of sound.

In stereophonic operation, a pair of enclosure bodies 10 each containing the above mentioned components is connected to an amplifier into which audio frequencies are fed. The enclosure bodies 10 may be located back to back or separated in a suitable room. The pair of speaker sys- 4 tems will produce satisfactory stereo effects at each point in the circumference of a circle having the pair of speaker systems located at its center. The stereo effects will be completely balanced at all points in the circumference of the circle. The pair of enclosure bodies may be separated by distances varying from /2 to 10 feet and still produce a balanced stereophonic effect.

To check the properties of my speaker system for a single enclosure body, two tests were run for frequency response in a 360 range of position. One test was con ducted using an audio frequency generator with a constant 0.03-volt output fed into a 20-watt amplifier which in turn was connected to my speaker system.

A stationary microphone was placed 5 feet from the speaker system and was connected to a 70-watt amplifier which in turn was connected to an oscilloscope.

The microphone was moved in increments of 30 a full 360 around a radius of 5 feet from my speaker system. At each position, a frequency response test was run beginning with a 1000-cycle per second signal and increasing in frequency in increments of 1000 cycles per second each to a maximum of 10,000 cycles per second. In each case, the same response occurred throughout the entire 360".

The test was repeated at a distance of 10 feet between the speaker system and the stationary microphone, using a 0.06 volt output of the audio generator. Again, the same frequency response occurred at each 30 increment position throughout the entire 360 of rotation of the microphone.

Although I have described my invention in detail with reference to the accompanying drawing and specification illustrating a preferred embodiment of my invention, it is understood that numerous changes in the details of construction and arrangements of parts can be made without departing from the spirit and scope of the invention as hereinafter claimed.

I claim:

1. A loudspeaker system capable of producing sound waves of a givenvolume at various audio frequencies upon energizing said system with audio frequencies, said sound waves remaining substantially constant in volume upon radiating outwards at all points in the circumference of a given circle having the speaker system located in the circles center, comprising:

an enclosure body;

a full range speaker and a high frequency speaker located in spaced relation inside said enclosure body, said full range speaker attached to a lower plate member mounted at the bottom of said enclosure body and with its open end facing downwards, said lower plate member having a plurality of openings for guiding sound Waves, and the high frequency speaker attached to an upper plate member mounted at the top of said enclosure body and with its open end facing upwards;

a lower guide cone member located below said full range speaker with the top of the cone extending up into the speaker and forming a channel for passage of sound waves in conjunction with said lower plate member in all directions surrounding said enclosure body, said lower guide cone member having a solid surface and a generally concave shape in the direction of said full range speaker;

an upper guide cone member located with its top extending into the flared outer end of the high frequency speaker and forming a channel for passage of sound waves in conjunction with said upper plate member in all directions surrounding said enclosure body, said upper guide cone member having a solid surface and a generally concave shape in the direction of said high frequency speaker;

and spacer members maintaining said cone members in Paced position with respect to their respective p akers,

2. A loud speaker system according to claim 1 in which the lower guide cone member has a generally hyperbolic shape.

3. A loud speaker system according to claim 1 in which the upper guide cone member has a generally parabolic shape.

4. A loud speaker system according to claim 1 in which the lower guide cone member has a generally hyperbolic shape and the upper guide cone member has a generally parabolic shape.

5. A pair of loud speaker systems capable of balanced stereophonic elfects in combination, upon being energized with audio frequencies, at each point of the circumference of a given circle having a pair of loud speaker systems located at its center, comprising:

a pair of speaker enclosure bodies;

a full range speaker and a high frequency speaker located in spaced relation inside each enclosure body, said full range speaker attached to a lower plate member mounted at the bottom of each enclosure body and with its open end facing downwards, said lower plate member having a plurality of openings for guiding sound waves, and said high frequency speaker attached to an upper plate member mounted at the top of each enclosure body and with its open end facing upwards;

a lower guide cone member located below each full range speaker with the top of the cone extending up into the speaker and forming a channel for passage of sound waves in conjunction with said lower plate member in all directions surrounding each enclosure body, said lower guide cone member having a solid surface and a generally concave shape in the direction of said full range speaker;

an upper guide cone member located with its top extending into the flared outer end of the high firequen-cy speaker and forming a channel for passage of sound waves in conjunction with said upper plate member in all directions surrounding each enclosure body, said upper guide cone member having a solid surface and a generally concave shape in the direction of said high frequency speaker; and spacer members maintaining each of said cone members in spaced position relative to their respective speakers. 6. A pair of loud speaker systems according to claim 5 in which each lower guide cone member has a generally hyperbolic shape.

7. A pair of loud speaker systems according to claim 5 in which each upper guide cone member has a generally parabolic shape.

8. A pair of loud speaker systems according to claim 5 in which each lower guide cone member has a generally hyperbolic shape and each upper guide cone member has a generally parabolic shape.

References Cited UNITED STATES PATENTS 2,065,367 12/1936 Evans 18l31 2,694,462 11/1954 Robbins et al. 181-31 2,900,040 8/1959 Novak 181-31 FOREIGN PATENTS 1,075,666 2/1960 Germany.

653,263 5/ 1951 Great Britain.

STEPHEN J. TOMSKY, Primary Examiner. 

1. A LOUDSPEAKER SYSTEM CAPABLE OF PRODUCING SOUND WAVES OF A GIVEN VOLUME AT VARIOUS AUDIO FREQUENCIES UPON ENERGIZING SAID SYSTEM WITH AUDIO FREQUENCIES, SAID SOUND WAVES REMAINING SUBSTANTIALLY CONSTANT IN VOLUME UPON RADIATING OUTWARDS AT ALL POINTS IN THE CIRCUMFERENCE OF A GIVEN CIRCLE HAVING THE SPEAKER SYSTEM LOCATED IN THE CIRCLE''S CENTER, COMPRISING: AN ENCLOSURE BODY; A FULL RANGE SPEAKER AND A HIGH FREQUENCY SPEAKER LOCATED IN SPACED RELATION INSIDE SAID ENCLOSURE BODY, SAID FULL RANGE SPEAKER ATTACHED TO A LOWER PLATE MEMBER MOUNTED AT THE BOTTOM OF SAID ENCLOSURE BODY AND WITH ITS OPEN END FACING DOWNWARDS, SAID LOWER PLATE MEMBER HAVING A PLURALITY OF OPENINGS FOR GUIDING SOUND WAVES, AND THE HIGH FREQUENCY SPEAKER ATTACHED TO AN UPPER PLATE MEMBER MOUNTED AT THE TOP OF SAID ENCLOSURE BODY AND WITH ITS OPEN END FACING UPWARDS; A LOWER GUIDE CONE MEMBER LOCATED BELOW SAID FULL RANGE SPEAKER WITH THE TOP OF THE CONE EXTENDING UP INTO THE SPEAKER AND FORMING A CHANNEL FOR PASSAGE OF SOUND WAVES IN CONJUNCTION WITH SAID LOWER PLATE MEMBER IN ALL DIRECTIONS SURROUNDING SAID ENCLOSURE BODY, SAID LOWER GUIDE CONE MEMBER HAVING A SOLID SURFACE AND A GENERALLY CONCAVE SHAPE IN THE DIRECTION OF SAID FULL RANGE SPEAKER; 